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Why wire a network?

If you’ve taken a look at my home-project page, you’ll notice that much of what I have up has to do with the network. My mom actually asked me a question early on. She asked me (probably not in her exact words), why wire a network when you could just use wireless? In my research while I’ve been putting everything together, I’ve checked out a number of blogs and many comments asking, “why not just use wireless?” I wanted to take some time to spell out why I’d go through the trouble and expense of wiring a network. If you’re building or considering building your own home, this may also help you in understanding my reasoning.

Greater network capacity

I am wiring a gigabit network, that is to say, 1 billion bits per second. A wireless N network is listed as 300 mbps (300 million bits per second), and you probably won’t actually get wireless N (more on that later). What many people don’t seem to understand is that with wifi, your actual connection speed is split between the number of devices connected. That is to say, suppose you have 300 mbps and 10 devices connected. Then each device would share that same 300 mbps line.

On the other hand, my gigabit switch has 16 ports and a capacity of 32 gbps. If I connect 10 devices, each device is going to get 1000 mbps. There is no shared line.

Why would I need that speed? Well, suppose I made a raw rip of a DVD on my desktop, and I wanted to move it to my home theater computer connected to my TV. Currently, my desktop is connected wired to my wireless router, and my HTPC is connected via wireless G. It currently takes me about 45 minutes to move that 4 GB image from one computer to the other. If I had a gigabit network, it would take a minute or two.

Wireless N? Wireless G? Wireless B?!

Another thing people don’t seem to understand… not only is wifi a shared line (dividing your speed by number of connected devices), but in order to utilities a wireless N network, all connected devices must have wireless N interfaces. Suppose I have a wireless N network with two connected devices with wireless N interfaces. If I connect another device with only a wireless G interface, the other two devices will fall back to wireless G speeds as well. Now you have wireless G speeds divided amongst three devices. Wireless G is at 54 mbps.

The same is true for wireless B. If you connect one wireless B device, the entire network will fall back to wireless B. Wireless B is at 11 mbps, divided amongst the number of connected devices.

Mean while, each device connect to my gigabit network will have its own 1000 mbps line.

Interference and Wireless router placement

If you have wireless N, you’re not actually going to get 300 mbps. If you have wireless G, you’re not actually going to get 54 mbps. These are speeds you’d get under “ideal conditions”. In actuality, you’re probably never going to get “ideal conditions”.

Wireless can be thought of as people shouting and listening. Your wireless router can shout at a certain volume and has the ability to hear certain volumes. Your laptop’s wireless router can shout (not as loud as your router) and can hear (but not as well as your router). Any time you shout, you are probably having shout through walls, and you’ll lose about half your volume and the sound will be muffled.

To continue the analogy, there is also background noise. Your cordless phone is an air horn and your microwave oven is a jackhammer. Chances are, your laptop won’t be able to hold a conversation with your router with the jackhammer going, especially if you’re trying to talk through walls.

You can put an amplifier on your router. This will give your router a megaphone. If the amp also improves received signal, it means your router will also have a megaphone pointed at its ears. The router will be able to hear better, but it will also hear the jackhammer much more loudly too.

You can buy repeaters. Each time your router says “marco”, when the repeater hears the router, it says, “marco” in the router’s voice. When it hears your laptop say “polo”, it says “polo” in the laptop’s voice. One problem I used to have using a repeater was that the repeater was louder than the router. So, the laptop would always listen to the repeater rather than the router, even though the repeater was further away and had more latency and muffle.

If you use multiple repeaters to fill dead zones, you’re going to get into something called “repeater hell”. In this scenario, you have a router and two repeaters. Router says, “marco”. Repeater 1 hears router and says, “marco”. Repeater 2 hears router and says, “marco”. Repeater 2 hears repeater 1 and says, “marco”. Repeater 1 hears repeater 2 and says, “marco”… Now the repeaters are screaming “marco” at each other… and the router can’t hear anything over them.

With a wired network, if you want wireless too, you can use multiple routers on different sides of the house if you have dead zones in wireless. They have their own voice and their own line.

Better to do it now rather than later

Not really comparing one to the other, but if you want a wired network, NOW is the time to do it. Since this is a new build, I can wire the network before the sheet rock goes up. If you have a current build and want to wire a network, you’re probably going to try to go under the carpet (if you have carpet) or you’re going to have to saw through your sheet rock.

Connecting an external building

I’m going to have a garden office. I will connect the building by running an Ethernet run through metal conduit. The external building will have one gigabit line connected to the building’s own router. In order to do this wirelessly, I would have to purchase two fairly large outdoor directional wifi antennae and make sure they point to each other. These antennae may attract lightning. I’d need to take down the antennae prior to any hurricane (or else they’ll possibly be destroyed).

Actually, there’s nothing wrong with connecting external buildings wirelessly, and I actually considered doing it that way early on. Wireless mesh networking is actually pretty cool. However, I decided the gigabit speeds were worth the trouble of running conduit.

I should mention that buried cable is definitely susceptible to lightning too. Here is what I am doing to help the situation:

Bury the cable. It does help the lightning danger, but not much.

Surge protection. Put surge protection on both ends of the outdoor runs. This will possibly save your switches (and possibly your computer) in the event of a lightning strike. I am using these. It should be noted that, although surge protection helps, your surge protectors may fail, and you may still lose a switch.

Use metal conduit. It may not make sense to you, but use metal conduit instead of PVC. Metal conduit will protect your run from lightning by creating a Faraday cage around the cables.

Lightning rods else where? I am not doing this… but I guess this can help too.

Desktops come wired, not wireless

Pretty much every desktop these days comes with a gigabit ethernet port built in. Very few come with wireless, so you’ll have to buy wireless cards for each one.

Take a look at what I’ve put together…

In actuality, my house will have a gigabit wired network, an indoor wireless network, and an outdoor wireless network.

If you haven’t looked yet, sign into this site using Facebook (or you can register with an email address). Once I see you have signed in, if I recognize who you are, I’ll give you the ability to look at my Interests > Home Project page (nudge me if I don’t notice you). You can take a look at how I plan to wire the house and my network diagram. Let me know what you think.